1. Technical Field
The present invention relates to voice over Internet protocol (VoIP) service and, more particularly, to a network system and method which detour-connect a link for rapid link failure recovery when a link set for VoIP service fails.
2. Related Art
VoIP service is a voice communication service in a communication network like the Internet, which service employs an Internet protocol as a basic communication protocol. A phone for the voice communication service is called an Internet phone or Internet telephone. Due to the rapid commercialization and global spread of the Internet, VoIP service has become a common name for voice service in a voice over packet network (VoPN). In the future, if wire and wireless communication networks are integrated based on Internet protocol, VoIP service will be necessarily employed in most Internet services, such as e-mail, electronic commerce, teleconferencing, and home shopping, as well as voice calling.
There are three types of VoIP service: phone-to-phone, web-to-phone, and web-to-web, where web means an Internet phone.
The present invention relates to routing resetting for VoIP calling when a network failure occurs in an all-in-one system that employs a distributed media gateway.
With gradual diversification and specialization, VoIP gateways have developed from a form in which a signaling gateway is combined with a media gateway into a form that can be configured in mutually different networks. Assisted by the advent of a media gateway control protocol (MGCP) and the introduction of the concept of a media sever, diversification has led to a situation wherein there are various types of media gateways.
The VoIP gateway has advantages due to its various services and service expandability, but it may cause phenomena such as call setup failure and media transmission failure, depending on the reliability of the network. For this reason, the operational status of the media gateway is checked by checking a link between the media gateway controller and the media gateway, and the media gateway controller employs the operational status information to use a valid media gateway, thereby providing reliable VoIP service.
However, the media gateway controller does not take any action to ensure that the operational status during the link check time is reliable, or to prevent failure of the media gateway during VoIP service.
In the case of a VoIP service network which includes a media gateway controller and a media gateway, a link between the media gateway controller and the media gateway is checked to detect a link failure of the media gateway controller for detour connection, but there is a problem in that it is impossible to perform detour connection for a voice session that is currently connected.
Due to the limited time available to check the link between the media gateway controller and the media gateway, the link failure cannot be checked during a predetermined time period. If a short link check time is set to rapidly detect the link failure, the result is an excessive load on the media gateway, and thus it is difficult to efficiently use the media gateway controller to its full performance.